Coke Bottle Grips Real or Reproduction

[TheFizzer]

I want to sell these but want to advertise correctly. How can I tell if these are real or reproductions?

 

[fordmike65]

Is the jewel glass or plastic?

 

[TheFizzer]

I think they are glass but I think the reproduction ones are glass too

 

[piercer_99]

here are the ones on my 1941 Monark Rocket, you can compare them, I believe yours are very similar.

 

[bobcycles]

Some of the jewel grip repros are so close it is very hard to tell. It's fun when there's repop everywhere isn't it?

good times!